Check your tire pressure frequently.
I don't think that there is one piece of advice which is more important than this.
The Rubber Manufacturer's Association (RMA) lists improper tire pressure as the most important factor in shortening the length of tire's lives. It is the first in their list of recommended practices which they list as PART.
The RMA reports that under inflation produces needless stress on tires and increases their wear, lessens the control you have over the vehicle and increases your risk of an accident. A tire can lose up to half of its pressure and still appear to be normal.
Pressure which is too low will cause tires to overheat, especially at high speeds and greatly increase the chance of suffering a blowout.
You can check the pressure anytime the tire is cool for accurate reading
The morning is usually suggested, but if you have to drive to some place to check the pressure, you may get a distorted pressure check caused by the warming of the tire as you drive.
For people who carry cargo
If you frequently carry heavy weight you can check your approximate pressure without a tire guage if you make some preparation. At some moment when you vehicle is carrying nothing and has the correct pressure, measure the distance from the ground to the center of the wheel. Mark this on a wooden stick which you carry with you. Then, after you have loaded your vehicle, place the stick next to the tire and see if the center of the wheel falls below the mark on your stick. If so, add air to raise the centre to match the mark.
When you remove the load and need to drive without weight, repeat this process but release air from the tire until the center of the wheel matches the mark on your stick.
Heat, causes air to expand, thus, the pressure in your tire when it is hot is higher than when it is cold.
This is why you may arrive home with your tires seemingly normal and see them looking deflated in the morning.
This, gauge from AutoAnything.com, is one of the nicest of the new breed of easy-to-use Tire Gauges which I've seen around.
For most cars the best guide is your vehicle's manual.
Pay particular attention to whether the recommended pressure for tires is the same for the front and rear wheels. Depending on the design of the vehicle, there may be different tire pressures for front and back. Not following this may result in having difficulty in steering or swaying.
Check your spare tire too!
Always try to follow the manufacturer's recommendations unless you're prepared to have unexpected consequences, some of which can be dangerous.
Since September 2007 all new vehicles sold in the USA have been required, by law, to be equipped with Tire Pressure Monitoring Systems that will alert the driver when tire pressure drops by 25% or more.
Best wishes in keeping up your pressure ...
Visit Tire Information World's Exclusive Tire Care and Accessories Store.